Ankel E G, Homandberg G, Tooney N M, Lai C S
Arch Biochem Biophys. 1986 Jan;244(1):50-6. doi: 10.1016/0003-9861(86)90093-7.
We have examined the interaction between heparin and human plasma fibronectin using electron spin resonance (ESR) spin label methods. The titratable sulfhydryl groups of plasma fibronectin were modified with a maleimide spin label [Lai and Tooney (1984) Arch. Biochem. Biophys. 228, 465-473]. Addition of heparin resulted in a decrease in the maximum splitting value of the ESR spectrum of spin-labeled fibronectin from 66.8 to 64.3 G, suggesting that heparin induces a conformational alteration of plasma fibronectin. This heparin effect was noticeable at a heparin-to-fibronectin ratio of 20 to 1 and reached a plateau at about 100 to 1. Other sulfated carbohydrates were tested; dextran sulfate was found to be as effective as heparin but chondroitin sulfates were ineffective. The results presented suggest that the binding of heparin changes the molecular conformation of plasma fibronectin to a more relaxed or flexible state.
我们使用电子自旋共振（ESR）自旋标记方法研究了肝素与人血浆纤连蛋白之间的相互作用。用马来酰亚胺自旋标记修饰血浆纤连蛋白的可滴定巯基[Lai和Tooney（1984年），《生物化学与生物物理学报》228, 465 - 473]。加入肝素导致自旋标记的纤连蛋白的ESR谱的最大分裂值从66.8 G降至64.3 G，这表明肝素诱导血浆纤连蛋白的构象改变。在肝素与纤连蛋白的比例为20比1时，这种肝素效应很明显，在约100比1时达到平台期。测试了其他硫酸化碳水化合物；发现硫酸葡聚糖与肝素一样有效，但硫酸软骨素无效。所呈现的结果表明，肝素的结合将血浆纤连蛋白的分子构象改变为更松弛或更灵活的状态。
